Canon Eg-S Focusing Screen - EgS

The Canon Eg-S Focusing Screen with Super Precision Matte surface is optimized for wide-aperture lenses, specifically those that have a maximum aperture of f/1.8 ¥_ f/2.8. It¥?s best suited for users who frequently manually focus in dim light with fast lenses. Areas that are slightly out of focus will appear more out of focus, making it easier to tell when focus is right-on.

Note, however, that with lenses that have a maximum aperture smaller than f/2.8, a Super Precision Matte screen will appear dark and grainy.